The objectives of this proposal are to identify and isolate those hormones and biochemical factors required for normal ovarian development in mosquitoes. Once this goal is attained studies using in vivo and in vitro techniques will be used to elucidate not only the physiologically normal temporal sequence of these hormones but also their modes of action at the molecular level. It is expected that knowledge derived from this study will allow the intelligent and rational development of specific agents which will interfere with the normal reproductive cycle of these important vectors. Application of such agents could lead to more effective specific mosquito population control. Furthermore, the insights gained with mosquitoes as a model may be applicable to other insects and thus have broad biological and practical consequences.